What must all eligible first-term Airmen have approved for reenlistment?

The requirement for all eligible first-term Airmen to have an approved Career Job Reservation (CJR) program for reenlistment is essential in the context of their military careers. The CJR program is designed to manage the number of Airmen in specific career fields, ensuring that there are enough personnel to meet the needs of the Air Force while also controlling the number of Airmen being retained in certain job roles. By requiring that first-term Airmen obtain an approved CJR, the Air Force can maintain a balance between the inflow of new recruits and the retention of experienced personnel, supporting overall force readiness and operational effectiveness. This process ultimately helps to ensure that the Air Force has adequately trained individuals in crucial positions while also considering the career desires of its members.

Other options such as a promotion letter, application for reenlistment, and an end of service plan may hold importance at different stages of the reenlistment process, but they do not serve as the primary requirement for first-term Airmen specifically when it comes to securing their reenlistment through the CJR program. Hence, the CJR is the critical factor in facilitating first-term Airmen's continued service in their chosen career fields.